The present invention generally relates to computer networking, and more particularly to an interface for physical layer devices operating in a network. The present invention is particularly adapted for use in Gigabit Ethernet physical layer devices.
Those skilled in the art of local area networks (LAN) know that standards define the parameters of communication and vary depending upon the speed and type of operation that is being employed in the system., Even though individual LANs may employ one or more of various standards, they typically use a medium consisting of twisted copper wire pairs for the transmission and reception of data. It is generally a requirement that one or more pairs be used for transmission of data in one direction and one or more other pairs to receive data in the opposite direction.
As is also known to those skilled in the art, it is necessary to have an interface for providing serialized data on the pairs of wires for transmitting and receiving data that may not be in serial form when input to the interfaces. Depending upon the particular standard being used, there may be up to 28 pins of data that are input to the interface for a ten bit interface (TBI) or a Gigabit media independent interface (GMII) or a media independent interface (MII). These standards are set forth in Institute of Electric and Electronic Engineers (IEEE) standards identified as IEEE802.3u MII and IEEE802.3z GMII and the TBI.